diff options
author | Chris Metcalf <cmetcalf@tilera.com> | 2012-03-29 15:57:18 -0400 |
---|---|---|
committer | Chris Metcalf <cmetcalf@tilera.com> | 2012-04-02 12:13:29 -0400 |
commit | 8c92ba6c327ee5089dec1e92eaa82927bee63d6d (patch) | |
tree | 0604093dfc61953b629a0b0889b6549dc1797d6c /arch/tile/kernel/entry.S | |
parent | bfffe79bc29a9c4c817d5f51590961220e26db1a (diff) | |
download | op-kernel-dev-8c92ba6c327ee5089dec1e92eaa82927bee63d6d.zip op-kernel-dev-8c92ba6c327ee5089dec1e92eaa82927bee63d6d.tar.gz |
arch/tile: add "nop" after "nap" to help GX idle power draw
This avoids the hardware istream prefetcher doing unnecessary work.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'arch/tile/kernel/entry.S')
-rw-r--r-- | arch/tile/kernel/entry.S | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/tile/kernel/entry.S b/arch/tile/kernel/entry.S index 431e9ae6..ec91568 100644 --- a/arch/tile/kernel/entry.S +++ b/arch/tile/kernel/entry.S @@ -85,6 +85,7 @@ STD_ENTRY(cpu_idle_on_new_stack) /* Loop forever on a nap during SMP boot. */ STD_ENTRY(smp_nap) nap + nop /* avoid provoking the icache prefetch with a jump */ j smp_nap /* we are not architecturally guaranteed not to exit nap */ jrp lr /* clue in the backtracer */ STD_ENDPROC(smp_nap) @@ -105,5 +106,6 @@ STD_ENTRY(_cpu_idle) .global _cpu_idle_nap _cpu_idle_nap: nap + nop /* avoid provoking the icache prefetch with a jump */ jrp lr STD_ENDPROC(_cpu_idle) |